An eye tracker refers to a device that detects coordinates of a position that a user is viewing where the coordinates are output as digital data. This device may be known as an advanced-level Human-Computer Interface (HCI), such as a Head Mounted Display (HMD). Traditional eye tracker devices require several peripheral devices, such as a camera 10 with a charge coupled device (CCD) image sensor, an A/D converter 12, and a DSP chip 14 with an image processing algorithm therein, as shown in FIG. 1. In the traditional system, a user's eyes are irradiated with infrared rays 16 where images of the user's eyes are obtained by camera 10 and further processed.
In the traditional system, the eye's images obtained through the CCD camera 10 are applied to A/D converter 12 which converts the images into a digital signal. Thereafter, the converted digital signal is applied to digital signal processing (DSP) chip 14 (or a microprocessor) which in turn finds a center of the pupil of each eye through the image processing algorithm based on the digital signal.
The traditional eye tracker system, however, requires several peripheral devices resulting in an increase in component cost and printed circuit board (PCB) fabrication cost. Further, the CCD and the DSP chip consume a large amount of power and are difficult to miniaturize. In addition, a long delay is required to identify a center of the pupil of the eye due to the limited performance of the traditional DSP chip and the image processing algorithm.
In view of the foregoing, it would be desirable to provide an integrated chip for detecting eye movement.